In hearing aid technology, the tendency more and more is to switch over to processing the audio signals digitally. The transmission of audio signals is effected by means of a digital signal processor unit, ultimately to an electrical/mechanical output coupler of the hearing aid. The transmission performance of the hearing aid between the acoustical/electrical input transformer and the electrical/mechanical output transformer will be constructed on the signal processor unit in such a way that individual hearing deficiencies through the hearing aid will be corrected as extensively as possible.
It is therefore fairly obvious that optimal advantage from such hearing aids can be exploited only if—in steps normally—a preliminary tuning of the hearing aid is made followed by a more precise tuning. During these adjustments the transmission parameters on the hearing aid are adapted to individual needs.
Normally the preliminary tuning occurs by use of diagnostic data, as from audiograms. By means of such data a primary tuning of at least one portion of the transmission parameters is effected on the hearing aid or at least the hearing aid type is selected.
Subsequently, the tuning is done in situ. Generally, an individual for whom one or two hearing aids are to be fitted is equipped with the hearing aids that are to be tuned and is subjected to audio signal tests. A hearing aid has already been applied to the individual mostly on the basis of the individual diagnostic data. The in situ tuning is then further conducted by means of the diagnostic data and/or on the basis of the assessments of the individual concerning practical experience hearing, that is, impressions from everyday life. On the basis of these details it is standard for the acoustics technician to choose one testing signal suitable for testing the individual's assessment from a number of available testing audio signals. This testing signal is presented over loud speaker to the individual with the fitted hearing aid and after a new assessment by the individual a tuning of at least one portion of the transmission parameters is undertaken on the hearing aid.
It is now clear that a manual precision tuning of the transmission parameters on the hearing aids, on the ear of the individual, is not manually feasible—as through a potentiometer operation. Therefore a communication connection to a tuning computer is produced on hearing aids of this type via a corresponding interface.
Based on the assessment by the individual, the computing device determines, among other things by way of a database, which transmission parameters are to be adjusted on the hearing aid and in what manner.
The experienced-based information is stored in the database—which of the aforementioned parameters is to be adjusted and in what manner—according to the aforementioned assessments. Also, algorithmic correlations between parameter settings and assessment will be considered, for example, between an assessment of “too loud” and the loudness increase of the parameters determining the loudness in the hearing aid.
In a more simple case, but not in the most optimal case, the assessment of the individual will result orally through a technician, such as a hearing aid acoustic technician. After the proper conversion, the technician will enter the corresponding data of the assessment into the tuner computing unit with a human input device, normally a computer keyboard.
In order to conduct the tuning procedure in situ as quickly as possible for the individual concerned and as efficiently as possible, a switch-over has been made to standardize individual reactions at least partially and transmit them not via the hearing aid specialists to the tuner computing device but rather directly. Human input devices are used with simple keyboard fields that allow the individual to input data, for example according to a scale. This input unit communicates directly with the tuner computing computer.
The tuning of digital hearing aids occurs increasingly according to psycho-acoustical perception values, and also loudness. Relating to this, reference is made to EP-A-0 661 905 according to U.S. application Ser. No. 08/720,748 of the same applicant as the present application. It is therein explained how the psycho-acoustical perception value “loudness” can be evaluated by an individual by scale and how a computing device, corresponding to the test signal reaction, sets transmission parameters in the hearing aid for the specific critical frequency bands of human hearing. This procedure is described extensively in the aforementioned document and is of importance for the present invention only insofar as it explains how a tuner computing device sets the parameters of the transmission performance in the hearing aid on the basis of scaled loudness indications from the individual.